Extra Credit Project: Coefficient of Friction

Measure the coefficient of static friction
between various substances

This project must be done by individuals.

Your job in this assignment is to
measure the
coefficient of static friction between
surfaces of various types.

You can measure the coefficient of
static friction between an object and
the surface on which it rests by simply
tilting the surface until the object begins to slip.
Make sure that you understand the principles
involved.

You must measure the coefficient of static friction
between your textbook's cover and at least 6 different
materials.
Two of these materials must be

another copy of the textbook

a quarter

but the others are up to you.
You should try to find at least one material with
a coefficient of static friction mu < 0.10,
and at least one with mu > 1.0.
For each material, make three trials.
Measure the angle to which you must tilt the textbook
in order to cause the object to slip in each trial,
and record all measurements.
Average the angles for each object and use the average
angle to calculate the coefficient of static friction.

Make a table which lists
the materials and their coefficients of static friction.
Discuss briefly the results -- do they make
sense?

Be sure to draw a picture of your setup.
Describe carefully each piece of equipment you
use.